Lighting Advice

[Don Kondra]

Perhaps it's the brand of bulbs you're using Ken ?

I was buying from Alzo Digital for photo work and decided to try them as shop lights

http://alzodigital.com/online_store/...tudio_kits.htm

and they don't give the same color of light as other fluorescents or incadescents ....

That's simply cuz you're used to the yellow cast of "normal" lights, just try the 5500k, you won't go back..

Cheers, Don

[Ken Fitzgerald]

Don,

You still can not get as good a coverage pattern with a single point globe style bulb as you can get with a 48" tube.

Using Jack's method I have no shadows in my shop.

To achieve the same coverage pattern with no shadows using the compact fluorescents as you are suggesting you would have to have a lot more sockets and if I have to use photo quality bulbs......aren't they more expensive?

In the end, if you have to use more globe type bulbs and sockets and use more expensive photo bulbs....what have you saved or accomplished?

[Don Kondra]

Hi Ken,

As my ballasts go I am replacing them with one light socket. So I am ending up with the same number of light sources.

I haven't actually researched whether the wattage rating of fluorescent tubes is based on tungsten equivalents.

But, my 45w CF bulbs (150w tungsten equiv) appear brighter than the tubes they replaced and as I said, I prefer the color of the light.

The price I quoted of $10/bulb is the photo quality CF twisty type, not the hot and short life Photoflood bulbs normally associated with photography.

So in a 26' x 36' shop I have 11 source points, where the 12th would have gone is a 10' x 10' spray booth with 3 source points on the interior walls.

That's 14 x 2 tubes = 28 + ~40 replacement tubes in 24 years.

For a new installation using an average of $50/T8's including tubes would cost me $700 compared to $210 for sockets and CF bulbs.

I hope I have the same amount of time left to test the life of the CF bulbs

Cheers, Don

[Ken Fitzgerald]

You cannot get the same pattern coverage from a single point source globe light that you can get from a 48" tubular light source. Thus you will end up with less light in some areas.

Now if you want to install them because you feel you save money....fine...

But if you are replacing a 48" fluorescent fixture with a single compact fluorescent bulb on a socket, you are in fact functioning with less light.

It really depends if you want an equally well lighted area or you want to save money.

But it really is apples and oranges.....not apples and apples you are comparing here.

[Jerry Bruette]

Thanks for all the excellent advice. Looks like another trip to the BORG for more fixtures...I bought only 5.

Ed the formula you're looking for is Watts/Volts=Amps. Then you can size your circuit accordingly.

Jerry

[Don Kondra]

Hi Ken,

I offer the dollar figures only as a matter of interest to anyone building a new shop.

My decision was based on a visual impression of quantity and quality of light. I did have a test period before I decided to change.

A ballast had gone and I wasn't planning a trip to town for a few days so I took the cover off the unit and wired in a socket and CF bulb.

This just happened to be above my stroke sander and I had less shadows and I seemed to be able to see the "scratches" better

Works for me.

Cheers, Don

[Ken Fitzgerald]

Don,

If you feel saving money is the most important factor, then your idea is good.

But....you will not get the same EVEN light pattern with a single point source globe bulb as you would with a 48" tube by replacing the 48" fluorescent bulb fixture with a single compact fluorescent globe type bulb and a socket. The physics aren't there.

So....if you want to save money...your idea is valid....

If you want even light......48" tubes spaced properly will provide a more even light pattern.

Jack Lindsey's article in February 2002 FWW was about providing good even lighting in a woodworking shop with little or no shadows....at least it did in mine.

[Bill Arnold]

...
If you want even light......48" tubes spaced properly will provide a more even light pattern.

Jack Lindsey's article in February 2002 FWW was about providing good even lighting in a woodworking shop with little or no shadows....at least it did in mine.

Amen! With the layout in my shop that I described earlier in this thread, I have to TRY to make a shadow somewhere.

[Don Kondra]

Don,

But....you will not get the same EVEN light pattern with a single point source globe bulb as you would with a 48" tube by replacing the 48" fluorescent bulb fixture with a single compact fluorescent globe type bulb and a socket. The physics aren't there.

My experience is obviously different than yours, no disrespect to Jack.

A single, brighter light source on a white painted 10' ceiling appears to be a better solution, for me.

Cheers, Don

[Ken Fitzgerald]

Don,

The physics just don't work out.

Think about this....a single point...or 48" of single points. There is absolutely no way you can get as even a coverage with a single point source globe bulb. Period.

The physics are not there.

I've been working with single point and fan beam radiations from radar to x-ray for 40 years.

The physics are not there.

When you start taking in account I squared R losses the argument gets even worse for your theory.

There is only one logical and justifiable reason for replacing a 48" tube with a single compact bulb.....it's cheaper and that is the only thing you can prove. Period.

You can stick to your guns but sir, with all due respect, you are wrong.

But if you are happy...so be it.

[David Wong]

When I laid out the lighting for my home, I purchased a digital light meter so I could get some sense of what lumen, lux, and foot-candles, really meant. I purchased this light meter http://www.amazon.com/Mastech-Digita...2469927&sr=8-1. The light meter helped me specify how many foot-candles I wanted in various rooms. Surface of the sun lighting can be great for some tasks, but it could also make your eyes very tired if your whole shop were lit that way. Try spending any amount of time in a well lit retail store in the mall to see what I mean.

Armed with a quantitative number for your desired light level and if you are ambitious, you can also use a tool I found on the web named "CalcZone". This tool takes photometry data on a light fixture, and allows you to specify room geometry and a desired light level. It will then tell you visually how many light fixtures you will require. The tool is not that easy to use and requires some study. I found the tool on Lightolier.com (this tool is available on other lighting company web sites as well). The easiest way to use it is to find a light fixture on the site that is close to what you are using (e.g. 4 ft fluorescent 2- tubes F32T8 32W ea.). If the fixture has a photometry file associated with it, click on calculate and the tool will launch. While the tool is only a rough approximation of actual conditions, you can see some pretty interesting results. You can go into the Advanced Luminaire tab to tweak the settings for your light fixture.

I am not a qualified lighting anything - just a guy that became frustrated by the lack of specificity and vague advice everyone gave me about lighting. A really good book I can recommend on general lighting (but not shop lighting) is Residential Lighting - A Practical Guide, by Randall Whitehead.

[David Wong]

Jerry,

Just for fun I ran the CalcZone tool on your space 13 x 23. I assumed an 8 ft ceiling height, and a white ceiling with white or light colored walls. I used an industrial 2 tube fixture as a starting point and tweaked it. The fixture has a downward reflector.

The first screen shot shows the layout to achieve at least 100 FC at the work plane surface of 30 inches above the floor. The actual is 107 FC.

Picture 4.jpg

This next screen shot shows the light level when using only 6 fixtures. The actual is 79 FC.

Picture 5.jpg

It has been a while since I ran this tool, so no guarantees on the accuracy of these results, but fun to experiment with. Enjoy...

[Don Kondra]

Don,

The physics just don't work out.

Think about this....a single point...or 48" of single points. There is absolutely no way you can get as even a coverage with a single point source globe bulb. Period.

The physics are not there.

Ken, if you care to read my posts carefully you will find I have not challenged or disagreed with your point.

I have simply stated my experience and preference as a full time woodworker.

David, thank you for posting the CalcZone tool tip.

Between that and Jack's article I'm sure new shop builders can arrive at an appropriate set up based on their square footage.

Cheers, Don

[Jack Lindsey]

David - What LLF did you use? Did you input a CU or did the program calculate one?

[Nathan Callender]

Here's been my experience. I put 2 double florescent fixtures suspended from my garage ceiling (walls and ceiling all white, 8 ft). I used the cheap ones at HD I think 80W total. During the day, this adds a decent amount of light and at night, it's quite bright. The light is also pretty even with what I would call minor, soft shadows. I work mainly in the middle of the garage. I have thought about adding more light, but I don't want the main work area to be SUPER bright. Too much light just adds to fatigue for me.

One of my main gripes about the strip lighting is that it does really provide a soft, even light. I'm not really sure if that's preferable in a workshop. It makes it much harder to see imperfections in the wood, IMO. So, whenever I am doing detail work or sanding, or need more light in general, I use a 500W worklamp and position it to rake across the piece to show all the imperfections (a real ego killer !).

I have to say that I'm intrigued with the CF lamp idea. I think having a mixture between the two might be the key for me because I definitely see the benefit of having some directional light to add dimension to whatever it is I'm working on.

Does this jive with anyone else's experience or am I just weird? :-)